At this point, especially after Thursday's new trailer, we all know thatAvengers: Endgameis definitely going to be difficult to watch. The almost certain death of at least one or two beloved heroes will leave a dark cloud of grief hanging over the entire movie, but this tragedy should not come as a surprise to any of us. Not only has a sad conclusion for Endgame been set up by the events of Infinity War, but the ending could have actually been teased all the way back in 2015, during Avengers: Age of Ultron.

Think back to the conversation the Avengers are having in Age of Ultron, after the first attack, when Tony first name-drops Endgame. Remember what he says? "That up there, that's the endgame. How were you guys planning on beating that?"

The exchange that follows is a solemn reminder of the tragedy to come in Endgame, most likely involving the two very heroes having the conversation. To answer Tony's question, Steve simply says "Together." Every time the Avengers have done something together, they've succeeded. Until Infinity War, that is, when they proved that they were mortal after all.

Tony quickly retorts, "We'll lose," suggesting that whatever is up in space is greater than the sum of all their parts. Tony has a bleak outlook on this, but he has a point. However, it's Steve's next line that really sets the stage for what's to come.

"Then we'll do that together, too."

Just as they win together, they'll lose together. Steve suggests that the team will do whatever it takes to stop the threat of what's to come, as long as it's in an effort to save the people of Earth. This line teases the potential death of the Avengers, specifically Captain America and Iron Man, ending their stories side-by-side on the battlefield.

These heroes are forever intertwined, both in life and in death.

What do you think will happen in Avengers: Endgame? Could Captain America and Iron Man both die by the time all is said and done? Let us know your best theories in the comments!

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